If there was a drinking game based on the number of times the gangsters, molls and even law-enforcement officials betray one another on Boardwalk Empire, all the players would be drunk within the first 10 minutes. But it's the duplicity that keeps us coming back, and the past three seasons have provided a satisfying batch of deceit and intrigue out of Roaring Twenties Atlantic City. In anticipation of the HBO drama's season finale this weekend, here is a refresher on some of Enoch "Nucky" Thompson and Co.'s shadiest dealings to date.